Motor vehicle doors or hatches are expected to not only possess sufficient strength but the interior space created between outer sheet and inner sheet is also expected to be sealed against moisture. The approach pursued to this effect in practice is that the outer sheet is bent around the inner sheet, using one bordering tool or more so that the edge of the inner sheet is bordered by the outer sheet. An adhesive is brought into the bordering to achieve sufficient strength. A sealing adhesive is applied over the seam in the area of the free edge of the outer sheet in order to seal the bordering against moisture. Both adhesives have to be warmed-up at the restrained edge of the motor vehicle door or hatch to achieve sufficient strength and tightness.
It is known practice to connect edges of overlapping sheet metal plates by way of laser welding. One application of this method a laser beam is pointed into the gap created between these two sheets in such a manner that this laser beam is reflected several times and that the material of both sheets smelts in the area of the gap (vide EP 0511 746). If required, an additional material may also be brought into the gap (vide DE 434 1255).